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Topic: Open air fermentation (Read 8040 times)

I've been flirting with the idea for open air fermentation for a while, especially with Wheat Beers. I currently have a dunkle in a frig at 60 F, and was wondering if open air fermentation in a frig is going to give me the desired effect, and it's also in a carboy. Just brewed it this morning, so already I have I nice yeasty top. What do you think I could expect just popping the airlock off for the next 4 or 5 days til the trub sinks? BTW my latest Dunkle is with 3068 Weihenstephan Weizen. My desired effects are drive the esters up and keep the banana out. I want a more over all fruity with out excessive banana. I have perfect control on fermentation temp. Will there be enough air circulation in a frig and with the carboy? Others have said I could get better esters from 3638, but I've never used it.

I don't think you're going to get the result you want using the carboy. With what little experience I have with open fermentation, I like using a bucket. More air can get in around the krauzen. I think fermenting as low as 60 with 3068, you'll probably kill off much banana anyway. I always ferment at 68 to get more banana with that strain.

I would add that you should probably get your fridge REALLY clean, sanitized, and dry before doing an open fermentation.

Better yet - if the area right outside the fridge is (around) ferm. temps, leave it out of the fridge (or just leave the door open), allow it to free-rise to around 68F, then stick it in the fridge to make sure it doesn't creep up above 70F (to control banana-flavor). This will give your open fermentation the most room to "breath" during the most critical, flavor-developing portion of fermentation.

Yes, I saw that episode of Brew TV and it's what pushed me to want to try an open air fermentation. Thanks for the advice, some others have told me about the frig being one of the more questionable environmets to open air ferment also. Thank you every one.

Brew Your Own's latest issue has an excellent article on this topic. They say to wait for autumn nights when the temperature drops to about 40F. Brew your beer as normal, but leave the lid off the boil kettle at the end and let the lot wort cool for about 12 hours. Then rack into the carboy or bucket, and pop on the airlock. You could also set out several small pots of hot wort in various locations to use as "starters." If you're a techie, you can also leave out petri dishes of agar to catch the wild microflora. One very important thing: you can get some nasty, harmful bugs (Salmonella, E. coli). Evaluate the fermenting wort by smell only for the first month. By then, the pH of the fermentation will have dropped enough to kill off any potential nasties. Then you can taste. I plan to try some open air fermentations very soon. I highly recommend a trip to Allagash Brewing in Maine. They've pioneered the open air fermentation with their "Coolship," which looks like a small stainless steel, open air swimming pool.

With all of this talk and articles I am going to have to finally give open air fermentation a try. A few months ago a friend in my brewclub made an SS open fermenter for another club member and also gave me one. It will fit a 5 gal. batch.

Thanks... Hate to admit it but I haven't had a chance to use it due to other projects (an Old English Ale aged in a bourbon barrel) and remodeling our basement where I ferment all of my beers. The barrel project is now behind me and the remodeling is almost done. One of the first beers I make when I start back up will be using this fermenter. A friend of mine also had one of these built and has made some serious beer with it, so I am anxious to give it try.

I have a keg with the top cut off but never converted to a keggle that I use as an open fermenter (two, actually). It is my favorite one. I only go closed for long fermentations. I wish I had a 1 1/2" tri clamp ferrell installed on the side. There are decent looking filters that can attach. I have been looking at this for a while for the solution: